A concordance is an index in which the words appearing in a document are entered with quotations of context. The reader who looks up a word in a concordance can use the quotations of context to decide which occurrences of the word might be of interest. A program to produce concordances has been available. It can produce the following types of output: a concordance in KWIC (Key-Word-In-Context) format; a concordance in KWOC (Key-Word-Out-of-Context) format; a word index; or a word frequency list. The program can accept an input data set consisting of lines entered with a text editor, each line containing a text fragment to be operated upon by the program in order to construct text fields or records. The input data can represent a continuous stream of text, like a book or journal article, or it can represent a collection of discrete text items, like those in a catalog or bibliography. The program can also accept as input a pre-existing file of formatted records. A number of program options have been provided: concordance lines may be sorted within indexed words; a format may be defined for KWOC output; keys may be constructed from multiple fields; words may be specified for exclusion (or inclusion); word definition may be modified, etc. The description of input data and the specification of program parameters are made with problem-oriented statements and do not require changes to the concordance program.